ST 500 "Piranha" Operation Manual: Use Guidelines
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6.
Monitor signal presence, watching the level bars in the table.
7.
If radio traffic is detected in any band, it is necessary to investigate the observed signals.
To do this, set the cursor to the desired band and activate the "ANALYSIS OF DETECTED
SIGNALS" function.
Signs of "THREAT" signal while analyzing frequency bands used by digital mobile
communications devices ("MOBILE DEVICES MONITORING" function):
high levels of a detected digital signal (in the absence of legitimate mobile communications
devices nearby)
time-frequency structure of the signal different from the standard pattern (while analyzing
with the oscilloscope)
an analog signal detected, that correlates with the test sound
Signs of "THREAT" signal while analyzing the ranges of mobile telecoms base
stations ("BASE STATIONS MONITORING" function):
time-frequency structure of the signal different from the standard pattern (while analyzing
with the oscilloscope)
an analog signal detected, that correlates with the test sound
Signs of "THREAT" signal while analyzing the user list ("USER LIST" function):
at the frequency of the detected signal, the test sound is heard through the headphones
the test sound is not heard in the headphones, but the oscilloscope picture of the
demodulated signal changes with the test sound
there is a radical decrease in the level of the detected signal when ST 500 is brought
outside the room
9.1.4. LOCALIZATION OF THE SOURCE OF DETECTED SIGNAL
If the listening device uses an open transmission channel, an
acoustic
or
energetic
method is
used for localization. Localization of the source of the encoded signal is produced only by the
energy method.
When using the
acoustic method
, the operator turns on the test sound source, moves it
around the room (listening to the demodulated signal in the headphones) and searches for the
place in the room where the signal is heard best.
For more accurate localization, it is recommended to knock lightly on interior items located
near this place. A knock will be heard quite well in the headphones.
Energy method
is to determine the place in the room where the signal level will be
maximum. The analysis is performed using indicators that are implemented in various modes of
the SELECTIVE HF DETECTOR:
"PANORAMA" or DIFFERENTIAL mode, "FIXED FREQUENCY ANALYSIS" function (fig.12, 2)
"AUTOMATED" mode table (fig.14, 4)
"WIRELESS COMMUNICATION" mode, "ANALYZING DETECTED SIGNALS" function (fig.19,
13)
Having determined the place in the room where the signal level is maximum, it is necessary to
use the "SET "0" function (3.2.2). This will allow to more accurately determine the location of the
eavesdropping device.
